Evacuator with motive fin

Abstract

An evacuator is disclosed, and includes a body defining a central axis, a converging motive section, a diverging discharge section, at least one suction port, and at least one Venturi gap. The Venturi gap is located between an outlet end of the converging motive section and an inlet end of the diverging discharge section. The evacuator also includes a fin positioned within the motive section of the body. The fin extends in the direction of the central axis.

What is claimed is: 
     
       1. An evacuator, comprising:
 a body defining a central axis, a first tapering portion and a second tapering portion defining a passageway through the body, at least one Venturi gap located between an outlet end of the first tapering portion and an inlet end of the second tapering portion, and a suction port in fluid communication with the Venturi gap, wherein the outlet end of the first tapering portion defines an elliptically-shaped first opening into the at least one Venturi gap; and 
 a single fin protruding inward into the passageway and extending in the direction of the central axis with a length from a starting point at the inlet end of the first tapering portion or an intermediate position within the first tapering portion to an ending point at the outlet end of the second tapering portion or an intermediate position within the second tapering portion; 
 wherein the fin is either continuous through the Venturi gap or discontinuous at the Venturi gap. 
 
     
     
       2. The evacuator of  claim 1 , wherein the fin is discontinuous at the Venturi gap and defines a first face at the outlet end of the first tapering portion and a second face at the inlet end of the second tapering portion; and wherein a perimeter length of the second face is greater than a perimeter of the first face. 
     
     
       3. The evacuator of  claim 2 , wherein the inlet end of the second tapering portion defines an elliptically-shaped opening, and the fin has a generally semi-elliptical or semi-circular shape as a cross-sectional shape thereof. 
     
     
       4. The evacuator of  claim 3 , wherein the cross-sectional shape of a second portion of the fin in the second tapering portion has a larger height and or width than a first portion of the fin in the first tapering portion. 
     
     
       5. The evacuator of  claim 1 , wherein the fin is integral with the body. 
     
     
       6. The evacuator of  claim 1 , wherein the fin has a variable height along a length of the fin. 
     
     
       7. The evacuator of  claim 6 , wherein the fin has a maximum height proximate to the Venturi gap. 
     
     
       8. The evacuator of  claim 1 , wherein the first tapering portion is a converging motive portion and wherein the second tapering portion is a diverging discharge portion. 
     
     
       9. The evacuator of  claim 1 , wherein a height of the fin gradually increases through the first tapering portion to a maximum height at or proximate the Venturi gap. 
     
     
       10. The evacuator of  claim 9 , wherein the height of the fin gradually decreases through the second tapering portion. 
     
     
       11. The evacuator of  claim 9 , wherein the fin has a generally semi-elliptical or semi-circular shape as a cross-sectional shape thereof. 
     
     
       12. The evacuator of  claim 1 , wherein the inlet end of the second tapering portion defines an elliptically-shaped second opening at the Venturi gap. 
     
     
       13. The evacuator of  claim 1 , wherein the fin has a generally semi-elliptical or semi-circular shape as a cross-sectional shape thereof. 
     
     
       14. A turbocharged engine air system, comprising:
 a device requiring vacuum; 
 a turbocharger having a compressor fluidly connected to an intake manifold of an engine; and 
 an evacuator defining a motive section having an elliptically-shaped motive outlet, a discharge section, and a suction port, the evacuator including a Venturi gap positioned between the elliptically-shaped motive outlet and an inlet end of the discharge section, the Venturi gap in fluid communication with the suction port, wherein the discharge section of the evacuator is fluidly connected to the intake manifold of the engine at a location downstream of the compressor, and the suction port of the evacuator is fluidly connected to the device requiring vacuum; and 
 a single fin protruding inward into the passageway and having a length from a starting point at the inlet end of the first tapering portion or an intermediate location within the first tapering portion to an ending point at the outlet end of the second tapering portion or an intermediate location within the second tapering portion; 
 wherein the fin is either continuous through the Venturi gap or discontinuous at the Venturi gap. 
 
     
     
       15. The turbocharged engine air system of  claim 14 , wherein the fin is integral with the motive section of the evacuator. 
     
     
       16. The turbocharged engine air system of  claim 14 , wherein a height of the fin gradually increases through the first tapering portion to a maximum height at or proximate the Venturi gap. 
     
     
       17. The evacuator of  claim 14 , wherein the fin has a generally semi-elliptical or semi-circular shape as a cross-sectional shape thereof. 
     
     
       18. A non-boosted engine air system, comprising:
 a device requiring vacuum; 
 an intake manifold of an engine; and 
 an evacuator defining a motive section having an elliptically-shaped motive outlet, a discharge section, and a suction port, the evacuator including a Venturi gap positioned between the elliptically-shaped motive outlet and an inlet end of the discharge section, the Venturi gap in fluid communication with the suction port, wherein the discharge section of the evacuator is fluidly connected to the intake manifold of the engine at a location downstream of the throttle, and the suction port of the evacuator is fluidly connected to the device requiring vacuum; and 
 a single fin protruding inward into the passageway and extending from having a length from a starting point at the inlet end of the first tapering portion or an intermediate location within the first tapering portion to an ending point at the outlet end of the second tapering portion or an intermediate location within the second tapering portion; 
 wherein the fin is either continuous through the Venturi gap or discontinuous at the Venturi gap. 
 
     
     
       19. The non-boosted engine air system of  claim 18 , wherein the fin is integral with the motive section of the evacuator. 
     
     
       20. The evacuator of  claim 18 , wherein the fin has a generally semi-elliptical or semi-circular shape as a cross-sectional shape thereof.